Back stop for bowling alley



Nov. 22, 1955 c. SHERMAN BACK STOP FOR BOWLING ALLEY Filed Oct. 19. 1951United States Patent BACK STOP FOR BOWLING ALLEY Kenneth Clark Sherman,Stonington, Conn, assignor, by mesne assignments, to General Dynamics(Iorporation, New York, N. Y., a corporation of Delaware ApplicationOctober 19, 1951, Serial No. 252,107

11 Claims. (21. 273-s3 This invention relates to improvements in backstops such as are used in the pits at the rear end of bowling alleys toreceive the impact of balls which have been bowled and of pins whichhave been knocked across the pit by bowled balls. It is an object of theinvention to provide a back stop structure which is very durable, whichdoes not vary in its manner of functioning, and which can be readilymodified to have the particular characteristics desired for anyparticular variety of bowling game. For example, in one type of game ifa hard-hit pin strikes the back stop and bounces back onto the alley insuch a Way as to knock down another pin, that other pin or pins soknocked down must be replaced on the alley before the next ball isbowled, whereas in another type of game all fallen pins are countedincluding those which are knocked down by pins bouncing back from theback stop.

A further object of the invention is to provide a back stop which issubstantially thinner than the customary structure. This feature may beof great value in cases where it is desired to install in an alley apin-setting apparatus which includes a mechanism for mechanicallyretrieving the bowled balls and fallen pins from the pit. It oftenhappens that when alleys are built, the back stops are practicallyagainst the wall of the building in which the alleys are located. Sincethe rules require that the front face of the back stop he thirty inchesfrom the rear end of the alley, the substitution of a back stop having athickness several inches less than that of the conventional back stopnowin use provides precious inches back of the back stop for theinstallation of mechanism for elevating balls and pins from the pit.

According to the invention, a back stopis provided which has an upperportion, roughly half, differing from the lower portion, the upperportion being designed to receive the impact of hard-hit pins which flyacross the pit with a horizontal or rising flight. The lower portion ofthe back stop is designed to receive the impact of the bowled balls andsuch of the pins as may be knocked across the pit in a descending path.

The upper portion of the improved back stop includes a rigid platehaving a resilient front face. The lower portion includes a thick sheetof rubber or the like which is flexible and is secured to the bottomedge of the rigid plate. In front of both plate and sheet hang a seriesof thin, flexible sheets of suitable tough material such, for example,as canvas. The upper parts of the sheets may, if desired, be stitchedtogether, but the lower parts hang free with thin air spaces betweensuccessive sheets to act as air cushions in helping to absorb thekinetic energy of the balls which strike the back stop.

The back stop may be supported by being hung from a shelf in the usualmanner or by being secured by fastening elements to the side walls ofthe alley pit. The choice of support will depend on the degree ofrebound desired for pins which strike the upper portion of the backstop. A rigid mounting of the plate will result in a greater rebound ofpins which hit it.

For a more complete understanding of the invention, reference may be hadto the following description thereof and to the drawing, of which Figure1 is a partial sectional view of a bowling alley including an embodimentof the invention;

Figure 2 is a front elevation of the invention from the directionindicated by the line 2-2 of Figure 1;

Figure 3 is a section on the line 3-3 of Figure 2, on a larger scale;

Figure 4 is a fragmentary section on the line 44 of Figure 3;

Figure 5 is a fragmentary horizontal section on the line 55 of Figure 3;

Figure 6 is a section somewhat similar to Figure 3, of a modified formof the invention;

Figure 7 is a fragmentary horizontal section on the line 7-'7 of Figure6; and

Figure 8 is a fragmentary section on the line 8-8 of Figure 6.

The rear portion of a bowling-alley 10 is illustrated in Figure 1,together with a pit 12' in which bowled balls and fallen pins aredisposed. The back wall of the alley is indicated at 14. A heavy plankshelf 16 customarily projects forward from the back wall between theside walls or kickbacks i8 and 24) of the alley. A back stop or pad iscustomarily suspended from the under face of the shelf 16 to receive theimpact of bowled balls and of pins which are knocked from the alley andacross the pit. This pad heretofore has usually consisted of arectangular board or frame to the front face of which is secured a thickpadding of any suitable material with a cover of leather, canvas or thelike to hold the padding in place. According to the present invention aback stop is provided which comprises a rigid plate 22 suspended by eyes24 from loops 26 which project downward from the under face of the shelf16. The plate 22 may be of any suitable material such, for example, asaluminum, steel, or wood. To the front face of this plate is secured afacing layer 30 of resilient material such as soft rubber, this layerbeing of substantial thickness so as to provide resilience to cause arebound 0n the part of the pins which may strike the plate area of theback-stop. The height of the plate is a little more than half the totalheight of the back stop.

The lower portion of the back stop comprises a flexible sheet 32 of softrubber or the like, this sheet being of considerable weight andthickness. In order to reinforce the lower margin of the sheet 32, atransverse bar 34 of magnesium or other suitable material is secured tothe rear face of the sheet near its lower edge.

A plurality of thin flexible sheets 36 hang down in front of andadjacent to the front 30 of the plate 22 and the heavy sheet 32. Thesheets 36 may be of any suitable material such as canvas, each she-etbeing suspended from its upper margin which is secured to the uppermargin of the plate 22. The bottom edges of the sheets 36 are preferablyhemmed as at 38 so that the lower portions of the successive sheets areslightly spaced from each other. Each sheet has a rectangular area ofapproximately the same size as the combined shape and area of the plate22 and heavy sheet 32. If desired, the upper portions of the sheets 36which cover the plate area of the back-stop may be secured together byquilt stitching, as indicated at 40 in Figures 5 and 7. The lowerportions of the sheets 36 are not connected in any way but hangindependently. The front sheet 42 is preferably not stitched to theother sheets but hangs freely from its upper margin.

In order to add to the inertia of the back stop as a whole when it ismounted to swing at its upper edge, as indicated in Figure 3, an inertiamember 46 may be hung edgewise from the shelf 16 immediately behind theplate 22. This inertia member 46 may conveniently be in the form of arectangular plate of metal, such as steel, of sufficient thickness togive the desired added inertia so that when the back stop is struck by aflying pin, it will not-be swung too far back as a result of the impact.In order to prevent clashing between the plate 22 and the inertia member46, I provide suitable cushions between these two members, the cushionsbeing mounted on either one or the other as found convenient. As shown,the cushions consist of two or more vertical strips 50 of rubber orother resilient material which are fastened by cement orotherwise to therear face of the plate 22, one strip being provided for each side marginof the plate 22. The freedom of the back stop to swing results in theabsorption of a considerable portion of the kinetic energy of rapidlymoving pins and balls which strike the back stop by the conversion ofsome of this kinetic energy into swinging movement of the back stop,such movement being checked by the inertia of the backing member 46.

In case the back stop is to be mounted in an alley which is to be usedfor a game permitting pins to be knocked down by other pins reboundingfrom the back stop, greater rebound may be had by rigidly mounting theplate 22 so that it will not yield at all. This may be done as indicatedin Figure 6 by providing a plate 52 which is similar to the plate 22except that it has a flange 54 extending around its periphery and mayalso have reinforcing ribs 55, the plate being of suflicient size to fitbetween the kickbacks 18 and 20 so that it can be firmly secured theretoand to the shelf 16 by lag screws or other suitable fastening elements.The heavy rubber sheet 32 is preferably suspended from an inertia plate46 instead of from the fixed plate 52. Thin flexible sheets 36 may besuspended from their upper margins as hereinbefore described so as tohang down in front of and adjacent to the plate 52 and the heavy sheet32. The upper portions of these sheets, except for the outermost, may bequilt stitched as indicated at 40 in Figure 7.

Without limiting myself to any particular dimensions, I have found thata plate 22 which is /1 inch thick is suitable for the purpose, suchplate having a facing layer of rubber inch thick. The heavy flexiblesheet 32 may be from /1 inch to an inch in thickness. The height of theplate 22 is preferably about 18 inches, the height of the rubber sheet32 being approximately inches with an overlap of approximately 2 /2inches. If the flexible sheets 36 and 42 are of canvas, it is preferableto employ at least 10 such sheets and sometimes a few more. Thestiffening strip 34 may be of any suitable material such as magnesiumand may be two inches wide and inch thick. This strip stitfens the lowercorners of the heavy sheet 32 so as to prevent rapidly moving balls frombending back a lower corner and passing beyond the back stop. It is tobe understood, however, that the foregoing dimensions, and materials,are given by way of illustration only and may be varied as may be founddesirable without departing from the scope of the invention defined inthe following claims.

I claim:

1. A bowling alley back-stop comprising a rigid rectangular plate with afront facing of resilient material, a heavy flexible sheet secured tothe lower edge of said plate and depending therefrom, and a plurality ofthin flexible sheets in front of said plate and heavy sheet and securedalong their upper margins to the upper margin of said plate.

2. A bowling alley back-stop as in claim 1, some of said thin flexiblesheets being of canvas.

3. A bowling alley back-stop as in claim 1, some of said thin flexiblesheets having hems along their bottom edges.

4. A bowling alley back-stop as in claim 1,- some of said thin flexiblesheets having the portions thereof which overlie said plate joinedtogether by quilt stitching, the lower portions of said sheets hangingindependently.

5. A bowling alley back-stop comprising a rigid rectangular plate with afront facing of resilient material, a heavy flexible sheet dependingfrom the lower edge of said plate, an elongated stiffening elementsecured to said sheet near the bottom edge thereof, and a plurality ofthin flexible fabric sheets hanging in front of and adjacent to saidplate and heavy sheet, said thin sheets being secured along their uppermargin to said plate and extending sub.- stantially from the top marginof said plate to thebottom edge of said heavy sheet.

6. A bowling alley back-stop comprising a rigid rec.- tangular plateswingably suspended at its upper edge, a layer of resilient materialoverlying the front face of said plate, a rectangular sheet ofheavyrubber hanging from the lower margin of said plate, an elongatedstiffening element secured to said rubber sheet along the lower marginthereof, a plurality of thin flexible sheets secured along their uppermargins to the upper margin of the plate, and an inertia memberswingably suspended immediately behind said plate.

7. A bowling alley back-stop as in claim 6, said inertia member being aheavy metal plate suspended edgewise.

8. A bowling alley back-stop as in claim 6, and cushion elements mountedbetween said plate and inertia member.

9. A bowling alley back-stop comprising a rigid rectangular plate havinga substantial layer of soft rubber secured to its front face, meanssupporting said plate in a vertical plane, an inertia plate swingablysupported edgewise behind and parallel to said rigid plate, and a heavyflexible sheet suspended edgewise from one of said plates.

10. Apparatus-as in claim 9, and a plurality of thin flexible sheetssuspended edgewise in front of and against said rigid plate.

11. A bowling alley back-stop comprising a rigid rectangular platehaving a substantial layer of soft rubber secured to and covering thefront face thereof, a thick sheet of soft rubber depending fromthe'lower margin of said plate, a metal stiffening bar secured to saidrubber sheet along the lower margin thereof, a plurality of canvassheets having their upper margins secured to the upper margin of saidplate and their lower edges substantially on a level with the lower edgeof said rubber sheet.

References Cited in the file of this patent UNITED STATES PATENTS714,970 Talbert Dec. 2, 1902 720,533 Mellen Feb. 10, 1903 1,035,658Talbert Aug. 13, 1912 1,976,932 Forsberg Oct. 16, 1934 2,531,167 SimpsonNov. 21, 1950

